Mounting system for envelope-die holders

ABSTRACT

An effectively self-centering and size-universal envelope-die and mounting system in which envelope dies are secured to mounting plates by clips which engage pre-located apertures in the sides of dies and radial slots in the mounting plates; coacting aperture locating and hole drilling jigs are also disclosed.

[111 3,797,351 [451 Mar. 19, 1974 United States Patent [191 Jones, Jr.

[ MOUNTING SYSTEM FOR ENVELOPE-DIE 3.570.345 3/1971 HOLDERS [76] Inventor:

Wilbur M. Jones, .Iiw, 6909 Lachlan Cir., Baltimore, Md.

Mar. 7, 1973 Apple No.: 338,953

Primary Examiner-Willie G. Abercrombie Attorney, Agent, or Firm-John F. McClellan, Sr.

[22] Filed:

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locating and hole drilling jigs are also disclosed.

UNITED STATES PATENTS 10 Claims. 7 Drawing Figures MOUNTING SYSTEM FOR ENVELOPE-DIE HOLDERS This invention relates generally to envelope manufacturing and specifically to improved envelope die and envelope die holder apparatus.

Envelope cutting requires heavy, long cuts, held to close dimensions so that the blanks cut will not jam when later fed through automatic folder-gluers. In the best modern cutting presses envelope dies are held to the mounting plates by a very old arrangement, cap screws inserted through the mounting plates and threaded directly into the base portion of the dies, in a direction generally parallel'with the cutting stroke. The cutting stroke is vertical, with the work positioned on a bed below the envelope die head.

Long-stroke strippers arranged adjacent the external peripheries of the envelope dies require that the dies be relatively thin.

Because of the thinness and consequent lateral flexibility of envelope dies, and because of the unyielding character of the old art holding arrangement, thegreat vibratory side loads and axial loads imposed in cutting stacks of envelope stock and complicated by unbalanced blade clearances sooner or later shear and break off the holding screws, allowing envelope dies to shift and produce quantities of defective, unusable envelope blanks, Eventually in such cases, if not detected, the envelope dies shift further and are destroyed when sufficiently misaligned, usually damaging adjacent parts and creating a safety hazard from flying fragments as it breaks.

Very high strength screws and special precautions in tightening and checking are essential to keepthis 'expensive and wasteful problem even partially under control. Not only are the screws subject to loosening and breaking during long production runs, but theymust be removed and reinserted each time another envelope die is attached to the backing plate, which can be frequently if different envelope sizes are run in successive moderate quantity lots.

Each size envelope die in the old art arrangement requires a unique set of mounting holes through the mounting plate. All envelope dies are generally cen tered, and each mounting plate must be capable of maintaining precise alignment in spite of the numbers of holes through it and the wear and tear of service.

Additional problems with the old art arrangement are encountered and time is lost in attempting to align existing holes in the bases of envelope dies with mounting holes to be drilled in the mounting plates. Time is also lost in orienting dies on the mounting plates to assure proper centering.

A principal objectof the present invention is to provide a generally improved and novel mounting system for" envelope-die holding.

. Another object is to provide envelope-die, holding. f

a mounting system for Another object is to provide a mounting system as described which holds envelope dies more reliably,

with drastically fewer failures through loosening or breakage of parts. I

A further object is to provide a mounting system as described which centers envelope dies of various sizes,

and types on a single mounting plate.

-Still another object is to provide a mounting system plate to accommodate various sizes of envelope dies is made unnecessary.

. And another object is to provide a mounting system as described in which need for drilling tapping screw holes edgewise into the bases of envelope dies is eliminated.

Yet another object is to provide a system as described in which attachments of the various partsare clearly accessible for installation and for inspection. And yet another object is to provide a drilling alignment jig for use .as part of the system, which enables even unskilled persons to do a passable job of aligning an installing envelope dies on mounting plates. 7

Further objects are to provide a systemas described which is safe, economical, and simple, which reduces die breakage and shop time, which facilitates production changeover, and which in net terms produces more envelopes at less cost.

In brief outline the system of this invention includes a mounting plate having envelope-die holding slots radiating from the center, an envelope die having holddown apertures transversely through the thickness parallel with the base, special clips having base slot and envelope die aperture engaging structure, and an aligning jig for use in producing holddown apertures in the envelope die. l

The above and other objects and advantages of the invention will become more readily apparent on examination of the following description, includingthe drawings in which like numerals indicate like parts.

FIG. 1 is an isometric view'of an envelope press, partly broken away to show details;

FIG. 2 is a sectional elevation detail of an old art en velope die mounting;

FIG. 3 is an isometricview, partly broken away, of an envelope die and mounting plate inverted;

FIG. 4 isan isometric detail of an aligning arrangement; V l t FIG..5 is an isometric detail of a drill jig in place on an envelope die;

FIG; 6 isan isometric view of a clip; and FIG. 7 is an elevation section of a mounted envelope die.

FIG. 1 shows the general arrangement of a modern strokes. After each cutting stroke fresh stock is placed on the bedplate under the die.

Resilient strippers, shown broken away, surrounding the periphery of the envelope die, are attached to mounting plate in the usual arrangement. The strippers,

. which protrudebelow the cutting edge 14 of the enveas described in which drilling of holes in the mounting lope die, securely hold the work during cutting and.

strip away the excess stock on the retraction stroke.

The mounting plate 16isscrewed or clamped to the ram R. i t

FIG. 2 shows the old-art arrangement bywhich an envelope die 12is secured to a mounting plate 16'. The envelope die is in effect an irregularly shaped loop of hardened steel tapered ribbon, the outline shape corresponding to the desired envelope blank shape. In section the envelope die has a narrow base 18 and a relatively long depth narrowing from the base to a cutting edge 14. The base has a series of the largest feasible diameter tapped holes 20 in the base perpendicular to the mounting plate. To mount the envelope die to the mounting plate according to the old art arrangement, the envelope die is first centered on the mounting plate and the hole locations are marked on the mounting plate 16 which is then removed and drilled with clearance holes 22 which are countersunk as at 24. The parts are then secured together by high tensile strength screws 26. As indicated, these are of the largest diameter which the thickness of the base can accommodate; in spite of all precautions, one or more screws will predictably fail in service after some period of use, permitting the envelope die to vibrate, shift, and eventually to break.

FIG. 3 shows the envelope die mounting of this invention, inverted for assembly or disassembly of the envelope die 12 to the mounting plate 16 using clips 26 which engage the overhang of slots 24 in the working face 28 of the mounting plate. The mounting plate is square in shape. The slots are equally spaced in angle Each of the slots 24 is T-shaped in section and all the slots, which are preferably at least four, as shown (eight radial portions) pass through the center and extend entirely across the mounting plate. I

The center of the mounting plate is provided with a hole 30 having working-face-counterbore structure represented by annular shoulder 32.- Notches 34 in annular shoulder allow lugs (not shown) on the hydraulic piston structure of the press to pass into the hole 30 to engage annular shoulder 32 when the mounting plate is rotated, retaining the mounting plate and envelopedie assembly on the press in position for cutting as shown in FIG. 1.

Center hole 30 also serves another purpose. T-s lots break through into the center hole, permitting the T- section 36 of clips 26 to be slid into the T-slots at the centerhole, and then radially outward along the slots to engage the envelope die 12.

Each clip 26 has an envelope-die-engaging portion comprising an angle 38 with a laterally disposed, fixed pin 40. protruding from an upright leg 42 of the angle in a direction parallel with the mounting plate face 28. The pin 40 engages a corresponding aperture 44 in the thickness of the envelope die. A cap screw 46 passed vertically through the base leg 48 of the angle 38 engages threads in the T-section of the clip and allows the clip to be tightened on the overhanging thicknesses 50, 52 of the structure defining the T-slot. The upright. portion 54 of the T-section 36 of the clip is made slightly shorter than the overhanging thicknesses of the T-slot structure to provode clearance for the tightening.

In spite of this tightening, very little bending load is imposed on pins 40, because: (a) the close fitting apertures 44 in the envelope die are made to lie at exactly the correct position by a special.pre-drilling arrangement locating the apertures laterally, (b) a special drilling arrangement preserves the exact base-to-aperture distance, (c) the tightening screw and base arm arrangement of the structure ofthe clips 26 provides. a swivel, allowing a desirable accommodation in pin engagement in the horizontal plane, and (d) the apertures 44, slots 24, clip faces, and pins 40, lie in parallel planes so that relative movement is possible without cramping.

FIG. 4 shows the first step in drilling the apertures.

section of the clips, but which has a hole 56 through the cross bar parallel with the close fitting slot engaging portion 58 aligns a hardened punch 60, inserted through the hole, for marking the inner face 62 of the envelope die 12 to be mounted. The envelope die is generally centered on the mounting plate and oriented to square as many inner face portions of the envelope die as possible with the mounting place slots. Following the marking operation, the mounting apertures are drilled in the envelope die.

FIG. 5 shows the aperture drilling operation. The envelope die is drilled using squared U-shaped drill jig fitted over the base and secured to it by a clamp screw 66 threaded through a tapped hole in one leg 68 of the U and pressing against the side of the base. The drill jig has a drill aligning bore 70 passing through both legs, 68 and 72 perpendicular to the depth of the envelope die. To prevent wear and to provide for drilling holes of various diameters as required for various envelope die sizes and thicknesses, but always at the same location, the drill entrance side of bore 70 has a drillfitting cylindrical bushing 74 secured by set screw 76 passing through the base 78 of the drill jig. After the apertures 44 are drilled and de-burred, the envelope die 12 is installed on the mounting base, ready for use.

A further and very important feature of the invention is that an envelope die drilled and held in accordance with this invention as described will thereafter effectively self-center itself on as'semblyQalways returning to the same position regardless of orientation with relation to the base. I

FIG. 6 and FIG. 7-show more clearly the clip structure and assemblyrelation which provide the'advantages disclosed, including the self-centering-The pivot axis 80 defined by clamp screw- 46 lies relatively close to the face of upright leg 42 from which fixed pin 40 protrudes, insuring that lack of parallelism between slot 24 and aperture 44 will not-appreciable affect centering of the envelope die 12. The T-section structure 36 of the clip 26 fits slot laterally and the height leaves the clearance previously noted to secure tight fit at 82 and 84 the clamping faces.

Before clamping, the pin 40, which itself preferably has a securing pin 86 passing through the assembly, is easily pushed all the way home in aperture 44, leaving no room for backlash. Side loads are taken by clip 26 in the inward direction, the resilience of arm 42 easingv shock on the mounting, and side loads in the outward' direction are accommodated by flexing of the envelope die and a resilient loop, avoiding shearing the fastening screw as in the old art. i f

A further advantage that the same mounting plate can, without modification, secure and center any number of different sized envelope dies, avoiding plate weakening, confusion of locating holes, undue plate wear, envelope die spoilage through embedded brokenoff screw ends which resist fishing out, and 'many other drawbacks of the prior art.

Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

A T-shaped jig 54 which is generally like the bottom T- What is claimed and desired to be obtained by United States Letters Patent is:

1. In an envelope die and mounting system including a generally loop-shaped envelope die having a base and tapering in section from the base to a cutting edge, and a mounting plate for holding the die in a press, the improvement comprising: the envelope die having a plurality of apertures through the thickness thereof, the base having a plurality of slots in a face thereof, and means for attaching the envelope die to the base by engaging plural of the apertures and plural of the slots.

2. In a system as recited in claim 1, wherein all said apertures and slots lie in parallel planes.

3. In a system as recited in claim 1, wherein the mounting plate has a central opening, wherein said slots radiate from the central opening with equal angles between the slots, wherein said slots have at least one overhang, and wherein the means for attaching comprise plural members, each having a crossbar structure engaging the overhang of a slot.

4. In a system as recited in claim 3, wherein each means for attaching includes an upright portion with a lateral protrusion therefrom engaging a respective aperture.

5. In a system as recited in claim 4, wherein a member pivotally engages the crossbar structure of a means I 6 for attaching with the lateral protrusion thereof.

6. In a system as recited in claim 5, wherein the slots comprise T-shaped slots having two overhangs, wherein the crossbar structure engage all said overhanging structure defining the T-shaped slots.

7. In a system as recited in claim 4, wherein all said means for attaching engage respective apertures from within said loop of the loop-shaped envelope die.

8. In a system as recited in claim 7, a T-section member havinga hole through the length of the crossbar thereof parallel with said member, and a device slidably fitting in said hole and having an end thereof arranged for marking a portion of the envelope die when the envelope die is on said mounting plate.

9. In a system as recited in claim 8, a squared U- section drill jig proportioned for fitting over the base section of said envelope die and having a bore through at least one arm of the U-section, for receiving a drill for drilling a said aperture in the envelope die.

10. In a system as recited in claim 9, a bushing secured in said bore.

, is l 

1. In an envelope die and mounting system including a generally loop-shaped envelope die having a base and tapering in section from the base to a cutting edge, and a mounting plate for holding the die in a press, the improvement comprising: the envelope die having a plurality of apertures through the thickness thereof, the base having a plurality of slots in a face thereof, and means for attaching the envelope die to the base by engaging plural of the apertures and plural of the slots.
 2. In a system as recited in claim 1, wherein all said apertures and slots lie in parallel planes.
 3. In a system as recited in claim 1, wherein the mounting plate has a central opening, wherein said slots radiate from the central opening with equal angles between the slots, wherein said slots have at least one overhang, and wherein the means for attaching comprise plural members, each having a crossbar structure engaging the overhang of a slot.
 4. In a system as recited in claim 3, wherein each means for attaching includes an upright portion with a lateral protrusion therefrom engaging a respective aperture.
 5. In a system as recited in claim 4, wherein a member pivotally engages the crossbar structure of a means for attaching with the lateral protrusion thereof.
 6. In a system as recited in claim 5, wherein the slots comprise T-shaped slots having two overhangs, wherein the crossbar structure engage all said overhanging structure defining the T-shaped slots.
 7. In a system as recited in claim 4, wherein all said means for attaching engage respective apertures from within said loop of the loop-shaped envelope die.
 8. In a system as recited in claim 7, a T-section member having a hole through the length of the crossbar thereof parallel with said member, and a device slidably fitting in said hole and having an end thereof arranged for marking a portion of the envelope die when the envelope die is on said mounting plate.
 9. In a system as recited in claim 8, a squared U-section drill jig proportioned for fitting over the base section of said envelope die and having a bore through at least one arm of the U-section, for receiving a drill for drilling a said aperture in the envelope die.
 10. In a system as recited in claim 9, a bushing secured in said bore. 